Controller.



No. 869,812. PATENTED 00129. 1907.

E. w. STULL. V

CONTROLLER.

APPLIOATION FILED AUG.17.1904.

5 SHEETSSHBET 1.

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ATTORNEY THE mmms PETERS 5a., \vnsumcnm nv c No. 869,812. PATENTED OCT. 29, 1907 E. w. STULL. CONTROLLER.

APPLICATION FILED AUG.17. 1904.

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lzy4seau'ra fd WITNESSES: INVENTOI? THE NoREIS PErERs ca, numummou, u. c

PATENTED OCT. 29, 1907.

E. W. STULL.

CONTROLLER.

APPLIGATION FILED AUG. 17. 1904.

5 SHEETS-SHEET 3- Fig.

/N VENT 0 Fmmezft WStl/LZZ ATTORNEY ma mmms PETERS 5a., WASHINGTON, D4 cv PATENTED OCT. 29. 1907.

E. W, STULL.

CONTROLLER.

APPLICATION FILED AUG.17.1904.

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Emmeffi WASiuZZ ATTO/PNE Y ms NORRIS r'srsras can, w/xsmwomn, D, c

PATENTED OCT. 29, 1907.

E. w. STULL. CONTROLLER.

APPLICATION FILED AUG.17.1904.

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INVENZ'OR Emmett WfiiuZZ THC NORRIS PETERS cz. \vAsHiNmoM, n. c

EMM ETT W.

STULL, OF NORWOOD, OHIO, ASSIGNOR TO THE BULLOCK ELECTRIC MANUFACTURING COMPANY, A CORPORATION OF OHIO.

CONTROLLER.

Specification of Letters fPatent.

Patented Oct. 29, 1907.

Application filed August 17. 1904:- Serial No. 221,027.

To all whom it may concern:

Be it known that I, Ennirr'r W. S'rULL, a citizen of the United States, residing at Norwood, in the county of Hamilton and State of Ohio, have invented certain new and useful liiipi'ov'eii'ieiits in Controllers, of which the following is a full, clear, and exact specification.

My present invention relates to improvements in systcins of motor control, and more particularly to motor controllers ol the type usually employed on electrically propelled vehicles.

The main object of my invention is to so organize a system of control. for a plurality of motors as to obtain a uniform acceleration of the motors through series and ')arallel connections and a further object is to improve the structural parts of the motor controller so as to reduce its cost of manufacture and increase its ciency.

The invention therefore consists, in one of its aspects, of the combination of a pair of motors, with means, such as a motor controller of the cylindrical type, for connecting said motors first in series, then short-circuiting part. of the field of each motor to increase the speed, then connecting each motor in series with part of the field of the other motor leaving the armature and remaining field of one motor in parallel to the armature and remaining field of the other motor, then connecting the motors in parallel.

The invei'ition in another of its aspects comprises a cinitrolling cylinder, a star-wheel mounted to rotate with said cylinder, and a spring-pressed pawl engaging said star-wheel, the periphery of said star-wheel being so formed as to offer greater resistance to the spring pressed pawl while passing from notch to notch during the forward movement of the controller cylinder than during the backward movement of said cylinder to obtain an improved snap action between positions during forward movement.

The invention further comprises an interlock be tween the operating cylinder and the reversing switch of the coi'itroller, which includes a cylindrical apron carried by the controller shaft and formed with an opening through which. the end of a pivoted lever is adapted to pass provided the cylinder is in its oil position, said lever being spring-pressed against a cam, which is constructed and arranged to force said lever end into said opening while the rcversi g switch is being moved from either of its operative positions to mid position or vice versa. but it will not hold the lever in said opening when the reversing switch is in its mid po sition. If the controlling cylinder is in any position other than its off position when. the reversing switch is attempted to be moved from one position to another, the lever will strike said apron and prevent such movement.

In another of its aspects my invention comprises a blow-out magnet, having its core attached to or formed integral with the casing of the controller and one of its pole pieces termed of a sheet of magnetic material, held in place on the core by means of positioning pins and a single bolt, the said plate preferably carrying a plurality of strips of insulating material, which, when the plate is in position on the core, fit between the fingers of the controller to form are deflectors.

The invention also includes an improved arc deflector formed of strips of insulatingmaterial mounted on rods passing therethrough, said strips being separated from each other the required distance by sleeves of insulating material mounted on said rods, which are held in position on their support by means of readily removable blocks through which the supporting rods pass.

The invention also comprises in a series-parallel controller a single rotatable cut-out switch, which is adapted to cut out one or more motors controlled by said controller, leaving the remaining motor or motors connected in circuit, so as to be controlled rheostatically. An interlock may also be provided for preventing the operating cylinder from moving past a predetermined position when my improved cutout switch is moved into a position to cut-out of circuit one or more of said motors.

In the accompanying drawings Figure 1 illustrates a front elevation of my improved controller with the easing cover removed, the cap plate being shown in section; Fig. 2 is a diagrammatic representation oi my improved system of motor control with the controller shown in development as is customary in illustrating such structures; Fig. 3 is a top plan view of the controller cap plate; Fig. 4 is a sectional plan view of the controller on the line 4% of Fig. 1.; Fig. 5 is a sectional plan view of the controller on the line 55 of Fig. 1; Fig. 6 is a side view of the lower part of the controller, showing the face view of my improved cut-out switch; Fig. 7 is a detail sectional view on the line 77 of Fig. l, illustrating the operating mechanism for the interlock between the cut-out switch and the controlling cylinder; Fig. 8 is a sectional plan view in detail of the mechanism shown in Fig. 7, the view being taken on the line 8-8 ol Fig. 1; Fig. 9 is a trout elevation of the blow-out magnet pole piece with the arc deflectors mounted thereon; Fig. 10, is a plan view of the device shown in Fig. 9; Fig. ll is a section on the line ll ll of Fig. 9; Fig. 12 is section on the line 12 12 of Fig. 9, and Fig. 13 represents diagrammatically the different circuit; combinations and connections made by the motor controller in its successive operative positions.

Referring to Fig. 1 the main controller cylinder is illustrated at 15. This cylinder has the customary contact segments 16, which are mounted on sleeves of com ducting material; said sleeves being insulated from the shaft 17. by a layer oi insulating material. The relatively fixed contact fingers which engage said segments are indicated at 18. These contact tinge l are preier ably made adjustable by means of adjusting screws 19 which will be hereinafter described. Mounted on the upper end of the shaft 17 an operating handle 18. which has a hooked lug l9 on its under side. engaging with the customary notched flange 20 formed on the cap plate 2]. 'lheflangeamlthe hooked lug-are so arranged that the handle can only be placed in position on the shaft 17 when the controller is at its off position; the hooked lug 19 then passing readily through the notch 22. The reversing switch 23 also has its shaft 24 extending through the cap plate 21. and on its irregularly shaped upper end is placed an operating handle 25. said handle being provided with a hooked lug 26 engaging the notched flange 27. The operating handle of the reversing switch can only be removed when the latter is in its mid or otf position. The handle 25 is so shaped. being bent upwardly at. 28. that it can not be placed in position on the shaft 24 in a reversed position. The motorman is thus prevented from operating the reversing switch in any other than the proper manner- thereby reducing the danger of the reversing switch being left in either of its operative positions when the motorman leaves the car.

As clearly shown in Figs. 1 and 4. the upper ends of the shafts 17 and 24 operate in bearings 30 and 3] respectively, which are bolted to the back of the controller casing at 32 and 33 respectively. Thus it is easy to remove the cap plate oi the controller by simply removing the operating handles and the screws 34 without deranging the relative positions of the operating cylinder and reve "ing switch. The lower end of the controller cylinder shait l7 operates in the step bearing 35. while the lower end of the shaft 24 of the reversing switch is supported in the bearing The reversing switch is provided with the customary contact segments. with which the contact fingers g and i1 engage. The arrangement of these contact lingers on opposite sides of the reversing switch cylinder is clearly shown in Fig. 5.

The interlock between the reversing switch cylinder and the operating switch cylinder of the controller will now be described. Reierring particularly to Figs. 1 and 4. it will be seen that the reversing switch cylinder is provided with a notched cam 4-1. the notches 42 therein corresponding to the operative positions of the reversing switch and the notch 43 corresponding to the oft or mic position of the said reversing switch. The lever ti pivoted at 45 is normally held against said cam by means of the spring 46. Said lever -14 is provided with a projection -17. which is adapted to enter the opening 48 in the cylindrical apron 49 carried by the operating cylinder shaft. only when the controlling cylinder is at its off position. In any other position of the controlling cylinder. when an attempt is made to move the reversing switch front one position to another. the projection 47 will strike the apron l9 and prevent any movement of the reversing switch. The notch corresponding to the mid position of the reversing switch is so shaped that the projection 47 does not enter the opening 48 when the reversing switch is in said position. Therefore when the reversing switch cylinder is it its mid position. the main operating cylinder is not locked against movement. It is only locked against movement while the position of the reversing switch is being changed. and the main cylinder must be in its off position before a movement of the reversing switch can take place. As shown the apron 49 is preferably formed integral with star-wheel 50. The star-wheel 50 has the notches on its periphery so shaped that during the forward movement of the controller; that is. the movement of the controller cylinder in a clock-wise direction (Fig. t) the pivoted spring-pressed pawl 51 is retarded much more in its action than during a backward movement of the controller. This is accomplished by-giving the side 52 of each of the projections on the periphery of said starwheel a sharper angle than the side 53 of said project ions. It will be seen that. during the forward movement of the controller the antiiriction wheel 5-1 on the spring pressed lever 51. has to climb a sharper angle than during the backward movement in order to pass the projections of said wheel. This gives a desirable snap action between the operative positions of the controller and tends to prevent a too rapid forward movement. of the cylinder.

The contact fingers of the controller are mounted on an insulating block 55 shown clearly in Fig. 5 and each finger consists of the spring strip 56, having a heavy contact mounted at its outer end, and fastened to the terminal 57 at its inner end by means of the bolt 58, said strip having its tension adjusted by means of the adjusting screw 19 passing through the bracket 59, which is also fastened in position by means of the bolt 58.

The blow-out magnet core is indicated at (50. said core being preferably formed integral with the back of the controller casing. The coil of said magnet is indicated at 61. The front; pole-piece of the blow-out magnet. formed of a single tlat plate of magnetic material of the shape indicated in Fig. l by broken lines, and in Fig. 9 by full lines. The said pole piece is held on the core 60, by means of the bolt (55, which pas es through the opening 66 of the plate (Fig. 9). and is held firmly against movement about the bolt (35, by means of the positioning pins 63 and 64-, which pass through the opening 67 and 68 formed in said plate (Fig. 9). It will thus be seen that the plate is readily removable by simply unscrewing a single bolt. The said plate (32 has one side almost; completely covered by insulating material 70, and mounted upon said strip on the side carrying said insulating material are the holding blocks 71 and 72 held in position by means of the screws 7 3. Through vertical openings in said blocks pass the supporting rods 7 t, upon which are mounted alternately strips of insulating material 75, and sleeves of insulating material 76. The sleeves of insulating material are cut to the lengths desired to separate the strips 75 of insulating material forming the arc deflectors to the required distance. in outer rod 77 passes through openings formed in the arc deflector strips and has mounted thereon sleeves of insulating material 76, similarly to rods 74. The strip of insulating material 78 to which each one of the insulating arc deflector strips is fastened is preferably employed to give the structure greater rigidity. The

material mounted on each of the vertical supporting rods is held tightly in position by means of the clamping nuts 80. This structure provides a very light, effective, cheap, while at the same time very eilicient arc deflector.

The sin glerotatable cut-out switch ior the motor is located in the lower part of the controller casing and has its operating shalt 85 extending through the side of said casing at 80. As shown in Fig. (3 the outer end of the shaft 85 is provided with a collar 87, carrying an index finger 88, which points to one oi the three operative positions of the cut-out switch indicated at 89, 90 and 91. Directly opposite these indicating projections is a notched flange 92, provided with notches corresponding to the different positions oi the out-out switch. The cut-out switch has its shaft end iormed irregular, similar to the end oi the reversing switch shait, and is operated by the reversing switch handle 25, the hooked lug extension oi said handle passing through the notches in the notched flange 92 in the diil'erent operative positions oi said switch. This construction prevents the handle irom being removed irom the end oi the shaft 85 when the cut-out switch is in. any oi its intermediate positions. Mounted upon the shait 85 (Fig. l), are collars oi insulating material 93 and 94; between which are mounted the contact sectors 95, 9G, and 97, shown clearly in dotted lines in Fig. 6. These contact sectors are adapted to be embraced by the relatively fixed spring contact .fingers 98, 99, 100, 101, and 102, which are mounted within the protecting box 103 and are connected in the motor circuit in a manner to be hereinaiter described. As the shait 85 is rotated, the contact sectors are moved into and'out of engagement with the spring contact fingers to cut out or cut in one or the other motor or pairs oi motors.

A. mechanical interlock between the cutout switch and the operating cylinder is preierably provided. The inner end oi shait 85 carries a collar 104 provided with a cam suriace which engages the spring pressed bell crank lever 106, pivoted about the vertical axis 107 and iorced into engagement with said cam surface by means oi the spring 108. The arm 109 oi the hell crank lever is normally maintained in the back part oi the controller casing in the position shown in Fig. 8, but when the shait 85 is rotated the cam 105 causes the bell crank lever to move about its vertical axis and throw the arm 109 into the path oi the lug llO carried by the collar 11, pinned to the lower end oi the shait 17. In the series-parallel controller shown this lug 110 occupies a position corresponding to the final series position, or final rheostatic control position, oi the motor controller cylinder. it will thus be seen that when the cut-out switch is operated to cut out one or more oi the motors, the remaining motor or motors may be operated rheostatically but the controller cylind cr is prevented by the locking arm 109 from moving past the final series position, thereby avoiding the possibility oi cutting the remaining motor out oi circuit by moving the controller cylinder into the parallel positions. By using such a simple construction oi cutout switch and interlock, I am enabled to economize space in the controller, to cheapen the cost oi production, to avoid the necessity l'or using a plurality of cutout switches, and also render it impossible to operate the cutout switch unless the motor circuit is opened at the reversing switch.

Reicrring now to Fig. 1, ll, M M and ill represent l. l l l l l l l the motors of a iour motor equipment, controlled according to my improved method oi control. The armatures oi said motors are represented by a, a a and a. The field coils of said motors are each divided into two parts, the fields of motor M being indicated by/ andf, of M byf andf M byf and/ and lli byf and f. In this diagram the motor controller, the reversing switch and the cut-out switch are shown in customary development. The controller contact fingers are represented by to c inclusive. The contact segments on the controller cylinder are represented by (Z to (2 inclusive, 0 e 0 e and f One row oi contact [ingers on. the reversing switch includes fingers g to g inclusive. The other row of contact fingers is indicated by 78 to 7L7 inclusive. The contact segments on one side oi the reversing switch are indicated by L to k inclusive, m m and m, and on the other side by n to inclusive, and 1), p and The coil oi the blow-out magnet is indicated as before at 01. The contacts oi the cut-out switch are shown at 98, 99, 100, 101, and 102, while the contact sectors which engage said contacts are indicated at 95, 96, and 97. The resistance connect ed in the circuit with the motors during the series operation and during the rheostalic operation oi a single motor or pair oi motors is indicated at R.

in the operation of my improved system oi motor control, as the motor controller is moved into its first operative position, indicated by the vertical dotted lines l1, a circuit is completed through the motors as follows. From the trolley T through the blow-out magnet coil (31, contact linger c oi the motor controller, contact segments (1 and (Z contact linger 0"", resistance R, contact 0 contact segments (1 and (2, contact finger 0 contacts 101, 97, and 102 oi the cut-out switch, contact finger g of the reversing switch; then supposing the reversing switch is thrown to the right, through contact segment is, where the circuit divides, one branch circuit being traced through the contact segment is, contact finger g, field f, and f oi the motor M, contact finger gr oi the reversing switch, contact segment contact finger g armature a oi motor M, through the contacts 99, 9G, and 100 oi the cutout switch, contact finger e oi the motor controller, contact segments (Z and (1 contact finger (7 to the point 120 where the circuit again divides, one branch being traced through the armature a oi the motor M contact finger 717- oi the reversing switch, contact segment n contact finger h field coilsf and f oi the motor M' contact; finger h oi the reversing switc-h, contact segments '71 and a, contact finger h, to ground at G. The circuit also branches irom the contact segment is in the reversing switch through the contact segment [6 contact finger field coil/ andf' oi the motor ill, contact finger g of the rev rsing switch, contact gment is, contact finger g, armature a oi the motor M to the point 121, irom which the circuit is completed as beiore. described. A branch circuit is also cornpleted irom the point 120 through the armature u" oi the motor M, contact finger h, contact segment 11, contact; finger h, field coilsf and f oi the motor 1 contact finger h contact segment it through the segment n, and finger h from which the circuit is completed to ground at G beiore described. it will be seen that the motors M and M are connected in parallel with each other in series with the motors ill f of said motors being cut out.

and M which are also connected in parallel with each other. The connections corresponding to this position of the motor controller are clearly shown in Fig. 13.

As the motor controller cylinder is moved forward through the second, third, and fourth positions, the

sections oi the resistance R are successively cut out until the motor controller is in the fiith position, indicated by the vertical dotted line 55. The motors are. thus connected in series in the manner indicated by the fiith position. Fig. iii, the resistance R being entirely cut out oi the circuit. in this position oi the controller the circuit irom the contact linger c is completed through contact linger c through the contact segments d d (I and e". As the ctnrtroller cylinder islnoved into its next operative position, the contact segments (Z and d are brought into engagement with the contact lingers c and e, and a shunt circuit is thereby thrown around a part oi each of the fields oi the motors as indicated in the. sixth position, Fig. 13. This shunt connection weakens the fields oi each oi the motors and thereby increases their speed.

in p; ing from the sixth position into the seventh position, in which, as shown in the seventh position, Fig. I, the armatures and part oi the fields oi one pair oi motors are connected in series with the remaining part oi the fields oi the other pair of motors, the controller passes through several transitional positions indicated at ll, (5", and (3, Fig. it}, in which the inotors are connected successively in series as shown in (5, correspoinling to the liith position of the controller; then in position o a shunt is thrown around the armatures and part oi the fields oi one pair of motors, leaving the remaining pair, such as M and M connected in series with the remaining part oi the fields oi the motors ME and M then in position ti", the series connection is broken at the point 122, corresponding to the contact lingers ta and c and contact segments (7 and 11 Fig. 2, then the armatures and remaining part oi the fields oi the motors M and M are connected in series with parts oi the fields oi the motors 1i and M by throwing a shunt around the armatures and parts, oi the fields oi the motors )l and M. This last step is accomplished by the engagement oi the contact st1 gments c and 0 with the contact fingers c and e" in Fig. 2. The controller is now in its seventh operative position, which ii desired, may be used as a running position, it being understood that the transitional position between the sixth and seventh positions are not running positions and should be passed over very rapidly. in passing irom the seventh position to the eighth position oi the controller, the series connection between the motors is first broken at the point 122:), corresponding to the multiple break between the contact lingm's 0", c". and e and the contact segments 6-, d, d, and (1 oi the motor controller in l ig. 2. This leaves the motors ME and M connected in series with the field coilsfandjoi the motors El and M the armature and field coils and This position is indicated at '7 Fig. 13. The motors M? and M are then thrown directly across the line in parallel. This is accomplished by a shunt around the field sections f andf oi the motors M and M and the connections are indicated at '7 Fig. 13. The next transitional position indicated by '7 disconnects the armatures and fields of motors M and M entirely from the circuit, preparatory to making the connections indicated in the eighth position, in which the pairs oi motors are connected in parallel across the line; that is to say, the position in which all oi the motors are connected directly aero s the line, each armature being in series with the entire field oi its motor. :in increase in speed oi the motors is obtained in passing irom the sixth to the seventh position, since the armatures and parts oi the fields oi each of the motors are connected in parallel, each pair being connected in series with the part oi the field coils of the other pair oi motors, thereby supplying additional. current through that remaining section oi the fields, which increases the magnetic field strength oi each motor to hold the speed down below that obtained when the motors are all in parallel, but permits a higher speed than that obtained when the motors are connected in series. The circuits corresponding to the final or eighth position oi the motor controller will now be traced on lig. 2. Starting with the trolley T through the blow-out coil til, contact linger ll), contact segment (1 contact segment (1, contact lingers e, and e to point 120, irom which the circuit may be traced through the armatures (F and a and fields f, f, f and f oi the motors Mr and MP, connected in parallel to the contact linger It", irom which circuit; is completed to ground at .G. From the contact segment cl, a branch circuit is also completed through the contact segments f contact. linger e contacts lOl, 97, and 102 oi the cutout switch to the contact finger 5 oi the reversing switch, irom which the circuit may be traced through the contact segments L", a, and If, lieldsf, f, f, and f, and armaturcs a and u oi the motors .\l and ii. in parallel to the point 121. .lllence through the contacts 99, 9e, and lllt) oi the cut-out switch to the contact linger e, hence through the contact lingers and c to the contact segment (I to ground, prcierably in the controller casing at G.

\Yhile l have shown my invention as embodying a specific type 01' motor controller and a system oi control for a iour motor equipment, .l. do not care to be so limited, as many changes and modifications may be made in the controller and number oi motors controlled without departing irom the spirit or scope oi the invention, and l aim in the appended claims to cover all such changes or modifications.

llaving thus described my invention, what I desire to claim and secure by Letters Patent is:-

1. In a system of motor control, a pair of motors and a motor controller constructed and arranged to connect the motors first in series, then short circuit; part: oi the field or each motor, then connect each motor in series with part; oi the field oi the other motor so that the armature and remaining field of one motor will he in parallel to the armature and remaining field oi the other motor, then connect the motors in parallel.

2. 111 a system oi motor control, the combination with a pair oi motors, oi a motor controller constructed and arranged to connect the motors in series and parallel relationship by first connecting them in series. then shortcircuiting the armature and part of the field of one motor, then connecting each motor in series with part of the field or the other motor with the motor armatures and remain ingfields in parallel, then connecting the motors in pan allelv 3;. In combination, a pair 0i motors, and a motor controller constructed and arranged to connect the motors in series and parallel by first connecting them in series, then connecting each motor in series with part of the iield of the other motor while severing the series connection between the motors, then cutting out the armature and part of the held of one motor, then short-circuiting the remaining field of the last mentioned motor, leaving the other motor connected directly across the line, then connecting the motors in parallel.

4-. In a controller, an operating cylinder, a reversing switch, and an interlock between the operating cylinder and the reversing switch comprising a cylindrical apron carried by the controller shaft and provided with an opening in its side, a pivoted lever arm, an end o which is adapted to enter said opening, a cam carried by the reversing switch against which said arm is yieldingly pressed, said cam being constructed to force said lever end into said opening as the reversing switch is moved from one position to another, but to permit said lever to withdraw from said opening when the reversing switch is in its off or in-' operative position.

5, In a controller, an operating cylinder, a star wheel mounted to rotate with said cylinder, and a spring pressed pawl engaging said star wheel, the periphery of said star wheel being so formed as to offer greater resistance to the spring pressed pawl while passing from notch to notch during the forward movement of the operating cylinder than during the backward movement thereof to obtain an improved snap action between operative positions during forward movement of the cylinder.

6. In a controller, a blowout magnet having one of its polepieces formed of a sheet of magnetic material, a plurality of strips of insulating material mounted on said pole piece to act as are deflectors, and means for holding said pole piece on the magnet core consisting of positioning pins and a. single bolt.

7. In a motor controller, a casing, a blowout magnet having its core tormed integral therewith, a removable pole piece attached to said core, and means for holding said pole piece in position comprising a plurality of positioning pins and a single bolt.

8. In a controller, a blow-out magnet, a pole piece there tor, and means for fastening said pole piece to the core of said magnet comprising positioning pins and a bolt, the whole'being so arranged that the pole piece will be held in a definite position on the core, but may be readily removed therefrom by the removal of a single bolt.

ll. In a. controller, a blowout magnet, a plate of magnetic material forming one of the pole pieces for said magnet, are deflectors carried by said plate l'orined of strips of insulating ma. rial mounted on rods passing therethrough and separated from each other the proper distance by sleeves oif insulating material mounted on said rods, and means :i'or fastening said rods to said plate.

10. In a controller, an arc deflector formed of strips of insulating material, rods upon which said strips are mounted, sleeves of insulating material on said rods acting as separating pieces lfor said strips, a supporting plate, and means vlfor fastening said rods to said plate.

11. In a controller, a magnet pole piece, and an are de ilector carried by said pole piece formed of strips oif insulating material mounted on rods passing therethrough, said strips being separated from each other the required distance by sleeves of insulating material mounted on said rods, the latter being held in position on said pole piece by readily removable blocks through which said supporting rods pass.

12. In a series parallel controller, a single rotatable cutout switch adapted to cut out circuit one or more of the motors controlled by the controller and connect the remaining motor or motors in circuit so as to be controlled rheostatically and means for controlling the motors rheostatically.

13. In combination, a plurality of motors, a controller [or controlling said motors rheostatically and in series and parallel combinations, a single rotatable cut-out switch lfor cutting out of circuit one or more of said motors and for connecting the remaining motor or motors in circuit so as to be controlled by said controller rheostatically only.

14-. In combination, a pair of motors; a series-parallel controller therefor, and a rotatable cut'out switch which when in a certain position cuts one motor out of circuit and connects the remaining motor in circuit to be controlled rheostatically by said controller, and when in another position cuts out the second motor and connects the first to be controlled rheostatically.

1 in combination, a pair of motors, a series parallel. controller therefor, and a rotatable cut-out switch which when in a certain position cuts one motor out of circuit and connects the remaining motor in circuit to be controlled rheostatically by said controller, and when in another position cuts out the second motor and connects the first to be controlled rheostatically, and a mechanical interlock between said series parallel controller and said cut-out switch operating to prevent the controller from moving past its series positions when the cut-out switch is in either 01' said cut'out positions.

l6. In combination, a plurality of motors, a controller for controlling said motors rheostatically and in series and parallel combinations, a single rotatable cut out switch for, cutting out of circuit one or more of said motors and connecting the remaining motor or motors in circuit so as to be con 'olled rheostatically only, and a mechanical interlock for preventing the controller moving beyond a predetermined position when the cut out switch is moved to cut out any motor.

17. In a motor controller, a reversing switch, the shaft o1 which has an irregularly shaped end, a handle adapted to fit said shaft end, a hooked lug on said handle, a notched flange with which said lug is adapted to co-act, a cutout switch having its shaft end shaped similarly to the revcrslng switch shaft end and provided with a similar notched flange, the whole being so constructed and arranged that when the reversing switch is in its of' position, the handle may be removed therefrom and employed to operate the cut out switch.

18. In combination, a pair oi motors, and means for connecting said motors in series and parallel relationship which includes means for accomplishing the intermediate step of connecting each motor in series with a field winding and not with the armature of the other motor.

19. In a system of motor control, a pair of motors and a motor controller constructed and arranged to connect the motors first in series, then connect each motor in series with but part of the field and not the armature of the other motor, and then connect the motors in parallel.

20. In a controller, an operating cylinder, a reversing switch. and an interlock between the operating cylinder and the reversing switch so constructed and arranged as to prevent movement of the operating cylinder as the re vcrsing switch is moved from one position to another but to permit such movement when the reversing switch is in its off or inoperative position.

21. in a controller, an operating cylinder, a reversing switch, and an interlock between the two, said interlock being constructed and arranged to prevent movement of the reversing switch save when the operating cylinder is in oft position, and to permit movement of the operating cylinder when the reversing switch is in either its ahead, back or oft position while preventing such movement when the reversing switch is not in one of such positions.

In testimony whereof I afiix my signature, in the pres once 01' two witnesses.

EMMET'I W. STULL.

Witnesses Fnnn J. KINsnr, Gnonon W. CAPPIN.

It is hereby certified. that in Letters Patent No. 869,812, granted October 29, 1907, upon the application of Emmett W. Stull, of Norwood, Ohio, for an improvement in Controllers, an error appears in the printed specification requiring correction, as

follows: In line 46, page 3, the reference numeral 11 should read 111; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 12th day of November, A. D 1907.

l o. o. BILLINGS,

Acting Commissioner of Pate'nls.

[SEAL] 

